Describe the effect that photosynthesizing prokaryotes had on the ancient atmosphere.

Photosynthesizing prokaryotes affected the ancient atmosphere by adding oxygen. In ancient times the oxygen level was .42%, compared to the 21% oxygen level now. Photosynthesizing prokaryotes have made the world livable today.

image result for how many calories of energy will 20 grams of carbohydrates provide in one gram provides 4 calories

consuming the right balance of protein, carbohydrates and fat can you maintain a healthy weight and optimize your energy levels. protein and carbohydrates both contain 4 calories per gram, while fat provides 9 calories per gram.

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